compat: backport to FreeBSD 12.2

This should allow us to get more testing coverage earlier.

This port here is also a bit janky. I really don't like the taskqgroup
business, having to copy and paste those structs. And this isn't well
tested, either. But, it's a start.

This distinguishes between compat.h and support.h, though both header
files are intended to operate in more or less the same way.  It's
important to keep some discipline between things that we're backporting
and things that aren't _yet_ upstream or are shims for OpenBSD.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/src/compat.h b/src/compat.h
new file mode 100644
index 0000000..649e7dc
--- /dev/null
+++ b/src/compat.h
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2021 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ *
+ * compat.h contains functions that are backported from FreeBSD's main branch. It is different from
+ * support.h, which is for things that aren't _yet_ upstream or from OpenBSD.
+ */
+
+#include <sys/param.h>
+#if __FreeBSD_version < 1300000
+#define VIMAGE
+
+#include <sys/types.h>
+#include <sys/limits.h>
+#include <sys/endian.h>
+#include <sys/socket.h>
+#include <sys/libkern.h>
+#include <sys/malloc.h>
+#include <sys/proc.h>
+#include <sys/lock.h>
+#include <sys/smp.h>
+#include <sys/gtaskqueue.h>
+#include <sys/socketvar.h>
+#include <sys/protosw.h>
+#include <net/vnet.h>
+#include <net/if.h>
+#include <net/if_var.h>
+#include <vm/uma.h>
+
+#define taskqgroup_attach(a, b, c, d, e, f) taskqgroup_attach((a), (b), (c), -1, (f))
+#define taskqgroup_attach_cpu(a, b, c, d, e, f, g) taskqgroup_attach_cpu((a), (b), (c), (d), -1, (g))
+
+#undef NET_EPOCH_ENTER
+#define NET_EPOCH_ENTER(et) NET_EPOCH_ENTER_ET(et)
+#undef NET_EPOCH_EXIT
+#define NET_EPOCH_EXIT(et) NET_EPOCH_EXIT_ET(et)
+#define NET_EPOCH_CALL(f, c) epoch_call(net_epoch_preempt, (c), (f))
+#define NET_EPOCH_ASSERT() MPASS(in_epoch(net_epoch_preempt))
+
+#undef atomic_load_ptr
+#define atomic_load_ptr(p) (*(volatile __typeof(*p) *)(p))
+
+struct taskqgroup_cpu {
+	LIST_HEAD(, grouptask)	tgc_tasks;
+	struct gtaskqueue	*tgc_taskq;
+	int	tgc_cnt;
+	int	tgc_cpu;
+};
+
+struct taskqgroup {
+	struct taskqgroup_cpu tqg_queue[MAXCPU];
+	struct mtx	tqg_lock;
+	const char *	tqg_name;
+	int		tqg_adjusting;
+	int		tqg_stride;
+	int		tqg_cnt;
+};
+
+static inline void taskqgroup_drain_all(struct taskqgroup *tqg)
+{
+	struct gtaskqueue *q;
+
+	for (int i = 0; i < mp_ncpus; i++) {
+		q = tqg->tqg_queue[i].tgc_taskq;
+		if (q == NULL)
+			continue;
+		gtaskqueue_drain_all(q);
+	}
+}
+
+#endif